Sound general and sports nutrition knowledge in athletes is essential for making appropriate dietary choices. Assessment of nutrition knowledge enables evaluation and tailoring of nutrition education. However, few well-validated tools are available to assess nutrition knowledge in athletes. The objective of the present study was to establish the validity of the Platform to Evaluate Athlete Knowledge Sports – Nutrition Questionnaire (PEAKS-NQ) for use in the United Kingdom and Irish (UK-I) athletes. To confirm content validity, twenty-three sports nutritionists (SNs) from elite, UK-I sports institutes provided feedback on the PEAKS-NQ via a modified Delphi method. After minor changes, the UK-I version of the PEAKS-NQ was administered to UK-I SN from the British Dietetic Association Sport and Exercise Nutrition Register, and elite athletes (EA) training at elite sports institutes in the UK and Ireland. Independent samples t-test and independent samples median tests were used to compare PEAKS-NQ total and subsection scores between EA and SN (to assess construct validity). Cronbach's alpha (good ≥ 0⋅7) was used to establish internal consistency. The SN achieved greater overall [SN (n 23) 92⋅3 (9⋅3) v. EA (n 154): 71⋅4 (10⋅0)%; P < 0⋅001] and individual section scores (P < 0⋅001) except Section B, Identification of Food Groups (P = 0⋅07). Largest knowledge differences between SN and EA were in Section D, Applied Sports Nutrition [SN: 88⋅5 (8⋅9) v. EA: 56⋅7 (14⋅5)%; P < 0⋅00]. Overall ES was large (2⋅1), with subsections ranging from 0⋅6 to 2⋅3. Cronbach's alpha was good (0⋅83). The PEAKS-NQ had good content and construct validity, supporting its use to assess nutrition knowledge of UK-I athletes.

Psychopathologists have failed to make significant progress toward understanding the causes of psychopathology. Despite the foundational importance of construct validity and measurement to our field, insufficient attention is paid to these concerns in the assessment of psychopathology vulnerabilities prior to their implementation in causal models. I review the current state of construct validity and measurement in psychopathology research, highlighting the lack of consensus regarding how we should define and measure vulnerability constructs. The limited capacity of open science practices to address these definitional and measurement challenges is discussed. Recommendations for progress are made, including the need for consensus agreement on (1) working definitions and (2) measures of vulnerability constructs. Other recommendations include (3) the need to incentivize ‘pre-clinical’ descriptive work focused on measurement development, (4) the formation of open-access databases designed to facilitate measurement evaluation and development, and (5) increased exploration of the use of novel technologies to facilitate the collection of high-quality measures of vulnerability.

In this paper, we evaluate the factorial validity of the Spanish short version of the Utrecht Work Engagement Scale (UWES–9) and assess its predictive validity with respect to self-assessed work performance. A total of 229 employees from educational institutions in Ecuador participated. Using a model comparison analysis, the unidimensional model exhibited an excellent goodness of fit, χ2 = 26.176 (24), p = .344; CFI =1.000; TLI = 1.000; RMSEA = .020; SRMR = .034; it was not improved by more complex models, Three-factor model: χ2 = 22.148 (21), p = .391; CFI =1.000; TLI = 1.000; RMSEA = .016; SRMR = .033. Two-factor model: χ2 = 26.080 (23), p = .297; CFI = 1.000; TLI = 1.000; RMSEA = .025; SRMR = .034). Therefore, it is justified as a unidimensional instrument of work engagement. However, upon analyzing the correlation patterns of the overall score and the work engagement dimensions in relation to the task performance, contextual performance, and counterproductive behaviors, we conclude that, while the unidimensional model exhibits a good fit, the three-factor theoretical approach is substantively superior in that it maintains differential predictive validity for each theoretical dimension.

Delay discounting paradigms have gained widespread popularity across clinical research. Given the prevalence in the field, researchers have set lofty expectations for the importance of delay discounting as a key transdiagnostic process and a ‘core’ process underlying specific domains of dysfunction (e.g. addiction). We believe delay discounting has been prematurely reified as, in and of itself, a core process underlying psychological dysfunction, despite significant concerns with the construct validity of discounting rates. Specifically, high delay discounting rates are only modestly related to measures of psychological dysfunction and therefore are not ‘core’ to these more complex behavioral problems. Furthermore, discounting rates do not appear to be specifically related to any disorder(s) or dimension(s) of psychopathology. This raises fundamental concerns about the utility of discounting, if the measure is only loosely associated with most forms of psychopathology. This stands in striking contrast to claims that discounting can serve as a ‘marker’ for specific disorders, despite never demonstrating adequate sensitivity or specificity for any disorder that we are aware of. Finally, empirical evidence does not support the generalizability of discounting rates to other decisions made either in the lab or in the real-world, and therefore discounting rates cannot and should not serve as a summary measure of an individual's decision-making patterns. We provide recommendations for improving future delay discounting research, but also strongly encourage researchers to consider whether the empirical evidence supports the field's hyper-focus on discounting.

Reliable and valid assessment of sports nutrition knowledge can inform athlete nutrition education to address knowledge gaps. This study aimed to test the reliability and validity of an electronically administered sports nutrition knowledge tool – Platform to Evaluate Athlete Knowledge of Sports Nutrition Questionnaire (PEAKS-NQ). A 94-item PEAKS-NQ was piloted to 149 developmental athletes (DA) in New Zealand, with a subset invited to complete the PEAKS-NQ again to assess reliability. Reliability was evaluated using sign test, intraclass correlation and Cronbach’s α. Accredited sports dietitians (ASD; n 255) completed the PEAKS-NQ to establish construct validity via known-groups methodology and provided relevance scores to determine the scale content validity index (S-CVI). Rasch analysis was conducted to identify potentially problematic items and test reliability. Score differences between DA and ASD were analysed using independent t or non-parametric tests. DA (n 88) were 17·8 (sd 1·4) years, 61·4 % female and mostly in high school (94·3 %). ASD (n 45) were 37·8 (sd 7·6) years, 82·2 % female, with >5 years of dietetic experience (59·1 %). ASD scored higher than DA in all sections and overall (91·5 (sd 3·4) v. 67·1 (sd 10·5) %) (P < 0·001). There were no differences between retests (n 18; P = 0·14). Cronbach’s α was 0·86. S-CVI indicated good content validity (0·88). Rasch analysis resulted in a fifty-item PEAKS-NQ with high item (0·91) and person (0·92) reliability. The PEAKS-NQ is reliable and valid for assessing sports nutrition knowledge which could assist practitioners effectively tailor and evaluate nutrition education.

The paper discusses the relevance of sufficient psychometric standards for dementia rating scales. The concurrent, convergent and construct validity of the Mini Mental State Examination (MMSE), the Alzheimer's Disease Assessment Scale (ADAS) and the CAMCOG are assessed. The Clinical Global Impressions and the Global Deterioration Scale are used as global scales. The concurrent and convergent validity are satisfactory. The construct validity expressed by the Cronbach and Loevinger coefficient are very good for all scales and subscales. The Mokken's single item coefficients show that the MMSE has the best individual hierarchical fit, the item reading can be left out. The ADAS is less uni-dimensional, eight items can be left out. The CAMCOG consists of too many items to apply the Mokken's single item coefficients or the Loevinger coefficient. Instead, the CAMCOG subscales are analyzed. This results in a possible reduction of the CAMCOG by 30 items to a total of 35 items. The factor analysis reveals two factors in both the MMSE and the ADAS while the number of observations does not allow a factor analysis of the CAMCOG to be performed.

The concept of electoral competition plays a central role in many subfields of political science, but no consensus exists on how to measure it. One key challenge is how to conceptualize and measure electoral competitiveness at the district level across alternative electoral systems. Recent efforts to meet this challenge have introduced general measures of competitiveness which rest on explicit calculations about how votes translate into seats, but also implicit assumptions about how effort maps into votes (and how costly effort is). We investigate how assumptions about the effort-to-votes mapping affect the units in which competitiveness is best measured, arguing in favor of vote-share-denominated measures and against vote-share-per-seat measures. Whether elections under multimember proportional representation systems are judged more or less competitive than single-member plurality or runoff elections depends directly on the units in which competitiveness is assessed (and hence on assumptions about how effort maps into votes).

Nutrient profiling (NP) is a method for evaluating the healthfulness of foods. Although many NP models exist, most have not been validated. This study aimed to examine the content and construct/convergent validity of five models from different regions: Australia/New Zealand (FSANZ), France (Nutri-Score), Canada (HCST), Europe (EURO) and Americas (PAHO). Using data from the 2013 UofT Food Label Information Program (n15342 foods/beverages), construct/convergent validity was assessed by comparing the classifications of foods determined by each model to a previously validated model, which served as the reference (Ofcom). The parameters assessed included associations (Cochran–Armitage trend test), agreement (κ statistic) and discordant classifications (McNemar’s test). Analyses were conducted across all foods and by food category. On the basis of the nutrients/components considered by each model, all models exhibited moderate content validity. Although positive associations were observed between each model and Ofcom (all Ptrend<0·001), agreement with Ofcom was ‘near perfect’ for FSANZ (κ=0·89) and Nutri-Score (κ=0·83), ‘moderate’ for EURO (κ=0·54) and ‘fair’ for PAHO (κ=0·28) and HCST (κ=0·26). There were discordant classifications with Ofcom for 5·3 % (FSANZ), 8·3 % (Nutri-Score), 22·0 % (EURO), 33·4 % (PAHO) and 37·0 % (HCST) of foods (all P<0·001). Construct/convergent validity was confirmed between FSANZ and Nutri-Score v. Ofcom, and to a lesser extent between EURO v. Ofcom. Numerous incongruencies with Ofcom were identified for HCST and PAHO, which highlights the importance of examining classifications across food categories, the level at which differences between models become apparent. These results may be informative for regulators seeking to adapt and validate existing models for use in country-specific applications.

Background and aims: Many sustaining traumatic brain injury (TBI) suffer ongoing post-concussion symptoms (PCS). The Rivermead Post-Concussion Symptoms Questionnaire (RPQ) is widely used, although there is disagreement about its structure. This study compared the fit of published RPQ structures with a four-factor structure derived from a large adult sample with TBI in Tasmania.

Method: 661 adults with TBI completed the RPQ at approximately one month post injury. Exploratory factor analysis (EFA), using the first half of the sample (n = 330), suggested a four-factor solution. This was compared with models reported in the literature with the second half of the sample (n = 331), using structural equation modelling. Trajectory of recovery across these factors was examined within subsamples at 1, 3, 6 and 12 months following TBI.

Results: Inter-correlations between items were strongest for somatic, cognitive and emotional functioning items and the EFA identified a four-factor model. Fit was examined utilising bootstrapping for model comparison. The data at 1 month following TBI best fitted the four-factor model (CFI = .95, RMSEA = .060 (.049–.071) and factors had adequate internal consistency (r = .61–.89). This model appeared a good fit and clinically useful across time points to 12 months post injury.

Conclusions: Data best fitted a four-factor model, identified using a rigorous statistical approach. Clinicians and clinical researchers may use this preferred model to provide more specific measurement of the severity of PCS. Future research could attempt replication within international samples.

Our objective was to determine whether a Symbol Search paradigm developed for functional magnetic resonance imaging (FMRI) is a reliable and valid measure of cognitive processing speed (CPS) in healthy older adults. As all older adults are expected to experience cognitive declines due to aging, and CPS is one of the domains most affected by age, establishing a reliable and valid measure of CPS that can be administered inside an MR scanner may prove invaluable in future clinical and research settings. We evaluated the reliability and construct validity of a newly developed FMRI Symbol Search task by comparing participants’ performance in and outside of the scanner and to the widely used and standardized Symbol Search subtest of the Wechsler Adult Intelligence Scale (WAIS). A brief battery of neuropsychological measures was also administered to assess the convergent and discriminant validity of the FMRI Symbol Search task. The FMRI Symbol Search task demonstrated high test–retest reliability when compared to performance on the same task administered out of the scanner (r=.791; p<.001). The criterion validity of the new task was supported, as it exhibited a strong positive correlation with the WAIS Symbol Search (r=.717; p<.001). Predicted convergent and discriminant validity patterns of the FMRI Symbol Search task were also observed. The FMRI Symbol Search task is a reliable and valid measure of CPS in healthy older adults and exhibits expected sensitivity to the effects of age on CPS performance. (JINS, 2015, 22, 1–8)